"I heard, Betsy," the intercom grille said. "That's not a lot of time."

"No kidding. How much fuel has the whole Skyport got; for our own flying, I mean?"

"At our current speed, a good ten hours. All the tanks were pretty full."

"Okay. Thanks."

"Still no word from ground control on your program," he added. "They're trying to look up the regs and track down the guy who's got the actual package, and doing both of them badly."

"Betsy?" Marinos again. "Sorry to interrupt, but it's Eric Rayburn on the shuttle. He wants to talk to you."

Whitney started to reach for the earphone he was wearing, but Betsy shook her head, stepping back to her chair and picking up her own set. "This is Kyser," she said into the slender mike.

"Liz, what the h.e.l.l's going on up there?" a harsh voice said into Whitney's left ear.

With the kind of crisis they were all facing up here, Whitney wouldn't have believed the tension on the flight deck could possibly increase. But it did. He could feel it in the uncomfortable shifting of Henson in his chair, and in Marinos' furtive glance sideways, and in Betsy's tightly controlled response. "We're trying to figure out how to get you and your pa.s.sengers out of there alive," she said.

"Well, it's taking a d.a.m.n sight too long. Or have you forgotten that John's in bad shape?"

"No, we haven't forgotten. If you've got any suggestions let's hear them."

"Sure. Just open this d.a.m.n collar and let me fly my plane back to Dallas."Betsy and Marinos exchanged glances; Whitney couldn't see Betsy's face, but Marinos's looked flabbergasted. "That's out of the question. You don't even know if the shuttle will fly any more."

"Sure it will! I've still got control of the engines and control surfaces. What else do I need?"

"How about electronics, for starters? You apparently don't even have enough nav equipment left to know where you are. For your information, you wouldn't be flying 'back' to Dallas, because we haven't left*we're circling the area at fifteen thousand feet and about two-seventy knots."

"All the better. I won't need any directional gear to find the airport."

Betsy's snort was a brief snake's hiss in Whitney's ear. "Eric, did you turn your oxygen off or something?

Neither you nor the shuttle is in any shape to fly. Period." Rayburn started to object, but she raised her voice and cut him off. "We know you're worried about your first officer, but once we make sure it's safe to dock again we can have doctors and emergency medical equipment brought aboard to take care of him."

"And then what? Try to land with me still hanging out your rear? Don't be absurd. Like it or not, you're eventually going to have to let me go. Let's do it now and get it over with."

"No," Betsy said, and Whitney could hear a tightness in her voice. "There are a minimum number of tests we'll have to run before we can even consider the idea. You can help by starting a standard pre-flight check on your instruments and systems and figuring out what's still working. Other than that, you'll just have to sit back and wait like the rest of us."

"Wait!" He made the word an obscenity.

"Skyport out." Betsy reached over and flipped a switch, then pushed her mike off to one side. Whitney couldn't see much more than the back of her head, but it was very obvious that she was angry. He shifted uncomfortably in his chair, wishing he were somewhere else. There'd been elements about the whole exchange that had felt like a private feud, and he felt obscurely embarra.s.sed that he'd been listening in.

"Don't let him get to you, Betsy," Henson advised quietly. "He's not worth getting upset about."

"Thanks." Already she seemed to be getting her composure back. "Unfortunately, he did hit one problem very squarely on the head."

"The landing problem?" Marinos asked.

Betsy nodded. "I don't know how we're going to handle that one."

"I don't understand," Whitney spoke up hesitantly. "You would just be separating off this module and landing it with the shuttle, wouldn't you?" A horrible thought struck him. "I mean you aren't thinking about landing the whole Skyport... are you?"

Betsy did something to her chair and swiveled halfway around to look at him. "No, of course not. There isn't a runway in the world that could take an entire Skyport, although the s.p.a.ce shuttle landing area at Rogers Dry Lake might be possible in a real emergency."

"Then what's the problem? The modules are supposed to be able to land on an eighteen-thousand-foot runway, and Dallas has to have at least one that's that long."

"The eighteen thousand is for a wing sections by itself, Peter," Marinos said patiently. He held up a hand and began ticking off fingers. "First: with the extra weight and*more importantly the extradrag*we'd have to put down at something above our listed one-sixty-five-knot landing speed.

That'll add runway distance right off the bat. Second: one of the weight savings on the wing sections is not having thrust reversers on our engines to help us slow down. We rely on landing wheel brakes and drogue chutes that pop out the back. With the shuttle adding weight out the back*and its gear will be at least a couple of feet off the ground when ours touches down, so there'll be a lot of weight*our balance will change. That means a little less weight on the front landing gear, which means a little less braking ability for those six sets of wheels. Maybe significantly less, maybe not; I don't know. And third, and probably most important: the drogue chutes come out the center and ends of our trailing edge*and we won't be able to use any of the center ones while the shuttle's in the way."

He shook his head. "I wouldn't even attempt to land on anything shorter than twenty-five thousand under conditions like this."

"I'd hold out for thirty, myself," Betsy agreed grimly. "We just don't know how much extra room we'd need. And don't bother suggesting we put down on a cotton field or straddling both lanes of Interstate 20. One of the other ways you save weight on a Skyport is in the landing gear, and landing on something too soft would tear it to shreds."

An idea was taking shape in the back of Whitney's mind... but he wanted to think about it before saying anything to the others. "So that leaves, what, the Skyport maintenance facility outside L.A.?" he asked instead.

"Or the one in New Jersey," Betsy said. "L.A.'s closer." She looked at her watch*the fourth time, by Whitney's count, that she had done so in the last ten minutes. "d.a.m.n it all, what's holding up ground control?"

As if in answer, the intercom suddenly crackled. "Bets, this is Aaron," a voice said. "We're ready here to start on down."

"Roger, Aaron; keep your line open," Betsy's voice said, too loudly, in Greenburg's ear. He resisted the impulse to turn down the volume on his portable half-headset; in a moment there would be another aluminum-alloy deck between them that should take care of the problem.

"Right. We're opening the access hatch now." As Lewis looked on, Greenburg undid the three clasps securing the surprisingly light disk and levered it up, making sure it locked solidly into its wall latch.

Feeling around the underside of the hatch rim, he located the light switch and turned it on. The blackness below blazed with light, and with a quick glance to make sure he wouldn't be landing on unstable footing he grasped the rungs welded to the hatch and started down the narrow metal ladder, tool belt banging against his thigh. The lowest of the Skyport's three decks was devoted to pa.s.senger luggage and general cargo and to the equipment necessary to move it from shuttle to Skyport, between wing sections where necessary, and back to shuttle again. The hatch the two men had chosen led to one edge of the cargo area, and most of the equipment in Greenburg's immediate area seemed to be motors and electronic overseers for the intricate network of conveyor belts and electric trams that sorted incoming luggage by destination and carted it to the proper storage area. All without human supervision, of course*and, despite that, it generally worked pretty well.

"The bay is straight back that way." Lewis had appeared beside him, clutching a sheaf of computer paper. "I think around that pillar thing would be the best approach."

They set off. Greenburg had been on a Skyport cargo deck only once, back in his training days, and was vaguely surprised at the amount of dirt and grease around the machinery they pa.s.sed. Within a dozensteps his blue jumpsuit had collected a number of greasy smears and he found himself wishing he'd had the extra minute it would have taken to change into something more appropriate for this job. But even a minute could make a lot of difference... and Bets was counting on them.

They reached the curved wall that was the lower half of the docking bay within a few minutes, arriving just forward of a wide ring bristling with hydraulic struts that Greenburg knew marked the position of the emergency docking collar. He glanced back at it as they headed forward under the wall's curve, wondering why the backup system hadn't worked. It should have kicked in as soon as the main collar's supports gave way.

"Watch your step," Lewis said sharply, and Greenburg paused in midstep, focusing for the first time on the dark-red puddle edging onto the path in front of him. Peering along the base of the wall, he could see more of the liquid, more or less collected in a narrow trough there. He squatted, touched it tentatively with a fingertip. It felt thick and oily. "Hydraulic fluid?" Lewis asked.

"Yeah. From the emergency collar, probably." Greenburg straightened and, with only a slight hesitation, rubbed the fluid off on his jumpsuit. Stepping carefully around the puddle in his path, he continued on.

The panel they'd decided on was precisely where the blueprints had said it would be: some two meters around the port wall from the heavy forward clamp machinery at the docking bay's forward tip. About forty centimeters by seventy, the panel sat chest-high in the wall and was, for a wonder, not even partially blocked by any of the conveyor equipment. Selecting a wrench from his belt, Greenburg began loosening the nuts.

"I hope there's nothing in here that can't take low air pressure," Lewis remarked as he untangled the two oxygen sets he was carrying and clipped one of the tanks onto the back of Greenburg's belt. "You want me to put the mask on you?"

"I'll put it on when I get this open," Greenburg grunted as he strained against a particularly well tightened nut. "I don't like stuff hanging from my face while I'm working. Distracts me."

"Put it on before you lose pressure in there, Aaron," Betsy's voice came in his ear.

"Aw, come on*Bets," he said, the last word a burst of air as the nut finally yielded. "We're only a thousand feet or so higher than Pikes Peak, and I've been climbing around up there since I was ten. I'm not going to black out up here for lack of air."

"Well... all right. But I want it on you as soon as you've finished with the panel."

"Sure."

It took only a couple of minutes to loosen all the nuts and, with Lewis's help, remove them and force the panel out of its rubber seating. For a minute there was a minor gale at their backs as the pressure inside the cargo deck equalized with that in the bay, and Greenburg realized belatedly he'd forgotten to check whether or not Lewis had remembered to close the hatch behind him. If he hadn't this windstorm was going to keep going for quite a while... but even as he finished adjusting his oxygen mask over his nose and mouth the rush of air began to subside and finally stilled completely. "Here goes," Greenburg muttered as, stooping slightly, he eased his head through the opening, blinking as a cold breeze swept his face.

It was an impressive sight. Even twisted too far toward the bay's starboard wall, the shuttle's nose still seemed almost close enough for him to touch as it loomed over him, vibrating noticeably in the incomplete grip the broken collar provided. To his left and only slightly below him, he could see that theshuttle's front landing gear had descended just as it was supposed to, and was hanging tantalizingly close to the extended forward clamp. Moving his mike right up against his oxygen mask*it was noisier in the bay than he'd expected*he said, "Okay. First of all, I can't see anything that could be interfering with the clamp or arm. Rick, do the telltales read the arm as fully extended?"

A short pause, then Henson's voice. "Sure do. It's still got lateral and vertical play, though. Want me to swing it around any?"

"Waste of time, as long as it's too short. Someone's going to have to go down there and take a look at it, I guess."

"That's not your job, though," Betsy spoke up. "Carl's lining up a mechanical crew to come up from the airport as soon as it's safe. They can do all the work that's needed in the bay."

"I'm sure they'll be thrilled at the prospect*and don't worry, I wasn't volunteering." Greenburg twisted his head around the other direction. "Now, as to the shuttle door... h.e.l.l. I can't be certain, but it looks like the edge of the collar is overlapping it*the shuttle must have slid back and then shot forward and starboard as the collar was engaging. What the h.e.l.l kind of guidance system error could have caused that?"

"We should know in ten or fifteen minutes," an unfamiliar voice put in.

"Who's that?" Greenburg asked.

"Sorry*maybe I shouldn't have b.u.t.ted in. I'm Peter Whitney; I'm helping to run the diagnostic program that will hopefully locate the problem."

"Peter Whitney?*ah, the McDonnell Douglas computer expert Paul Marinos had said he was bringing in. Have you got the program running yet?"

"Yes; a friend just radioed us the loading code."

"Well ahead of ground control's efforts, I might add," Betsy said. "We'll let you know when we identify the glitch. For now, let's get back to the shuttle door, okay? We think the sensors indicate hydraulic pressure problems in the emergency collar. Is there any chance we could fix that and get it to lock onto the shuttle? Then we could release the main collar and get the shuttle door open."

Greenburg shifted position again and peered at the top of the shuttle, wishing all the floodlights hadn't gone when the craft hit. "I don't think there's any chance at all," he said slowly. "As a matter of fact, it looks very much like the emergency collar's responsible for most of the c.o.c.kpit damage. It seems to have come out of the wall just in time for the shuttle to ram into it. If that kind of impact didn't do anything more than rupture a hydraulic line or two, I'll be very much surprised."

Betsy said something under her breath that Greenburg didn't catch. "You sure about that?" she asked. "I can't see any of that on the monitor."

"As sure as I can be on this side of the bay. I can go to the starboard side if you'd like and check through the panel there. Probably have to go over there to find out exactly where this fluid came from, anyway."

"Maybe later. Any other good news for us from there, first?"

"Actually, this is good news. Somehow, while the shuttle was rattling around the bay, it completely missed the Skyport pa.s.senger and cargo tunnels. If we can get everybody out of the shuttle, we can get them into the Skyport.""Well, that's something. Any suggestions on how we go about carrying out that first step?"

Greenburg frowned. Something about the shuttle was stroking the warning bells in his brain... but he couldn't seem to put his finger on the problem.

"Aaron?"

"Uh... yes." His eyes still probing the vibrating fuselage, Greenburg replayed his mental tape of Betsy's last question. "The, uh, side window of the c.o.c.kpit seems undamaged. It should be big enough for most of the pa.s.sengers to squeeze through. Of course, it's a four-meter drop or thereabouts, so we'd need to rig up some way to either get them down and then back up to the tunnel door or else to get them across to it directly. Maybe rig something up to the ski lift mechanism in the tunnel..."

His voice trailed off as the warning bells abruptly went off full force. The nosewheel was slightly closer to him!

"Bets, the shuttle's sliding backwards!" he shouted into the mike. "The collar must be slipping!"

For a few seconds all he could hear was the m.u.f.fled, indistinct sound of frantic conversation. Eyes still glued to the slowly moving nosewheel, he jammed his earphone tighter against his ear. "Bets, did you copy? I said*"

"We copied," Paul Marinos's voice told him. "Betsy's getting the shuttle to boost its thrust. Stand by, okay?"

Pursing his lips tightly under his oxygen mask, Greenburg shifted his gaze back along the shuttle to its main pa.s.senger door. If the collar was slipping he should be able to see the door slowly sliding further and further beneath the huge ring.... He still hadn't decided if it was moving when Betsy's voice made him start.

"Aaron? Is the shuttle still moving?"

"Uh... I'm not sure. I don't think so, but all the vibration makes it hard to tell."

"Yeah." A short pause. "Aaron, Tom, you've both done some shuttle flying, haven't you? What are the chances Rayburn could bring this one down safely, damaged as it is?"

Something very cold slid down the center of Greenburg's back. Betsy knew the answer to that one already*they all did. The fact that she was asking at all implied things he wasn't sure he liked.

Surely things weren't desperate enough yet to be grasping at that kind of straw... were they?

Lewis, after a short pause, gave the only answer there was. "Chances are poor to nonexistent*you know that, Betsy. He'd have to leave here at a speed of at least a hundred sixty-five knots, and with one or more windows gone in the c.o.c.kpit he'd have an instant hurricane in there. He sure as h.e.l.l won't be able to fly in that, and I personally wouldn't trust any autopilot that's gone through what his has."

"You can't slow down past a hundred sixty-five knots?" Whitney, the computer man, asked.

"That's our minimum flight speed," Lewis told him shortly.

"I know that. What I meant was whether you could try something like a stall or some other fancy maneuver that would pull your speed temporarily lower.""Wouldn't gain us enough, I'm afraid," Betsy said, sounding thoughtful. "Besides which, wing sections aren't designed for fancy maneuvers." She seemed to sigh. "We've got a new problem, folks. The shuttle's backwards drift, Aaron, was not the collar slipping. It was the last two supports bending, apparently under slightly unequal thrusts from the shuttle's engines."

Lewis growled an obscenity Greenburg had never heard him use. "What happens if they break? Does the collar fall off the shuttle?"

"The book says yes*but exactly when it goes depends on how fast the hydraulic fluid drains out.

My guess is it would hold on long enough to turn the shuttle nose down before dropping off and crashing somewhere in the greater Fort Worth area."

"Followed immediately by the shuttle," Greenburg growled. His next task was clear*too clear.

"All right, say no more. Tom, there should be a supply locker just forward of here. See if there's any rope or cable in it, would you?"

"What do you want that for?" Betsy asked, her tone edging toward suspicious.

"A safety harness. I'm going to go inside the bay and see if there's any way to get that forward clamp connected. Tom?"

"Yeah, there's some rope here. Just a second*I have to untangle it."

"Hold it, Tom," Betsy said. "Aaron, you're not going in there. You're a pilot, not a mechanic, remember?

We'll wait for some professionals from the ground to handle this."

"Wait how long?" he shot back, apprehension putting snap into his tone. "Rayburn can't keep firing his engines all day; and even if he could you have no guarantee the thrusts from all three turbofans would stay properly balanced. Do you?"

There was a short silence, during which Greenburg was startled by something snaking abruptly across his chest. It was Lewis, perhaps sensing the outcome of the argument, starting to tie Greenburg's safety line around him. "No," Betsy finally answered his question. "Rayburn's on-board can't give us those numbers any more, and the support stress indicators aren't really sensitive enough."

"Which means chances are good the shuttle's going to continue putting stresses on the clamps*variable stresses, yet. They're bound to fatigue eventually under that kind of treatment."

"Mr. Greenburg*Aaron*look, the program's almost finished running." Whitney, putting in his two cents again. "Once it's done we can have people up here in fifteen minutes*"

"No; only once we've found the problem and made sure the other wing sections don't have it. Who knows how long that'll take?" A tug on the rope coming off the chest of the makeshift harness Lewis had tied around him and a slap on the back told him it was time. Gripping the edges of the opening, he raised a foot, seeking purchase on the curved wall. Lewis's cupped hands caught the foot, steadied it.

Greenburg started to shift his weight... and paused. He was still, after all, under Betsy's authority. "Bets?